With a serrated knife, very carefully cut the bagels into slices between 1/8-inch and ¼-inch thick (8-10 slices per bagel). Spread in a single layer on baking sheets. Generously coat all over with cooking spray, garlic salt and pepper.

Bake until brown and crisp, 18 – 20 minutes. Let cool on pans.

Meanwhile, toss the cucumber with the salt in a colander; let drain 30 minutes.